1. Field of the Invention
This invention relates generally to tree control for items in hierarchical systems, and in particular, to a method, apparatus and article of manufacture for selecting multiple, non-adjacent items in a hierarchy and providing graphical feedback to the user on the state of the item selection.
2. Description of Related Art
Computer systems frequently organize data as hierarchical information structures. An example is a file system provided by a typical operating system. Usually, a file system contains a root directory, which consists of files and sub-directories. Each sub-directory also contains files and lower-level sub-directories. To aid a user in navigating between files and sub-directories, hierarchical structures are represented graphically as trees.
Relational database management systems (RDBMS) store data into tables. It is helpful if a user interface for an RDBMS represents hierarchical data therein in a tree-like manner. For example, the relationships between tables in a relational database, or the relationships between relational databases, may be hierarchical in nature. This is especially true when using replication services to create and/or maintain multiple copies of tables and/or databases.
Generally, a replication service creates copies of tables and/or databases from a primary system on one or more subscriber systems. The replication service feeds updates on the primary system to the subscriber systems on a continual basis.
During the execution of user dialogs that support various commands, the user may need to select from a large set of tables to participate in the command. Capabilities desired by the user include: organizing tables into a hierarchy that shows how tables are members of databases; selecting multiple items (e.g., tables); graphical information indicating membership of tables in replication groups; graphical information indicating how many tables in a database have been selected; and maintenance of table selection when database nodes are collapsed and tables are not visible.
However, the available controls for replication services do not provide all of the above capabilities simultaneously. Thus, there is a need in the art for a method of selecting multiple, non-adjacent items in a hierarchy in a manner that provides feedback to the user on selection status for both visible and collapsed nodes.
To overcome the limitations in the prior art described above, and to overcome other limitations that will become apparent upon reading and understanding the present specification, the present invention discloses a method, apparatus, and article of manufacture for a fractal nested layout in a hierarchical system
The present invention displays a visual hierarchy of items on a monitor connected to a computer. The items in the hierarchy can comprise either nodes or leaf items. Node items are, for example, directories, folders and databases. Examples of leaf items include files, tables, objects, documents, and spreadsheets. The hierarchy can include, for example, a higher level node in the hierarchy and several lower level nodes within an area of the higher level node. Lower level nodes are either expanded or collapsed. The collapsed nodes conceal their contents and the expanded nodes disclose their contents. The expanded nodes can contain several layers of lower level nodes that are visually formatted like the higher level nodes.
The invention provides a method, apparatus and article of manufacture for controlling the selection of items in a multi-level hierarchy in a computer. The method comprises displaying a hierarchy representing a replication group on a monitor connected to a computer, wherein the hierarchy is comprised of a root group node, at least one database node within the root group node, and at least one table sub-node within the database node, and wherein the replication group comprises a set of rules governing replication of tables represented by the table sub-nodes across a plurality of computer systems. The method further comprises selecting one or more database nodes and one or more table sub-nodes from the hierarchy to identify the databases and tables upon which an action is to be performed across the plurality of computer systems; updating the displayed hierarchy to denote the selected database nodes and table sub-nodes; and performing an action on the databases and tables represented by the selected database nodes and table sub-nodes in the displayed hierarchy across the plurality of computer systems. The method further comprises feeding updates to the databases and tables acted upon and represented by the selected database nodes and table sub-nodes in the displayed hierarchy on a continual basis. In one embodiment, the action performed on the databases and tables comprises initiation, termination, resumption or suspension of replication services. The invention additionally provides a method, apparatus and article of manufacture for selecting multiple items in a hierarchy having two or more levels as well as a method, apparatus and article of manufacture for displaying multiple selected items of a hierarchy. Preferably, the hierarchy comprises at least one replication group, wherein the items are replicatable on systems and the replication group comprises a set of rules governing the replication of items on systems. In one embodiment, the method comprises the steps of displaying a hierarchy of multiple items on a monitor connected to a computer, selecting two or more non-adjacent items in the hierarchy, and displaying graphical information on the monitor. The graphical information denotes the quantity of selected items and membership of the selected items in replication groups. In addition, the graphical information and item selections are maintained when the selected items are not visible on the monitor.
The displayed graphical information can be designed so as to provide the user with feedback as to the status of selected and/or non-selected items. The image of the icon can be designed to change as the status of the associated item changes. For example, in one embodiment, the displayed graphical information comprises a table icon that represents a table. The table icon can be designed to change when the represented table is selected. In another embodiment, the displayed graphical information comprises a database icon that represents a database. The database icon can be designed to change to a first image when all items within the database are selected, and the database icon changes to a second image when at least one, but less than all, items within the database are selected and a third image when no items are selected.
The displayed graphical information can include items that are not eligible for selection, or be limited to only those items eligible for selection. In one embodiment, the items comprise tables that are members of databases, and the displayed graphical information further denotes the membership of the tables in the databases. The displayed graphical information can comprise, for example, icons and text. In one embodiment, a first icon represents a database and a second icon indicates the presence or absence of a table within the associated database. The selecting can comprise selecting a replication group. Selecting a replication group results in selecting all items that are members of the replication group. In another embodiment, the selecting comprises selecting a database. Selecting a database results in selecting all items that are members of that database. Selecting a replication group selects all the tables in all the databases under that replication group.
Various advantages and features of novelty which characterize the invention are pointed out with particularity in the claims annexed hereto and form a part hereof. However, for a better understanding of the invention and its advantages, reference should be made to the drawings which form a further part hereof, and to accompanying descriptive matter, in which there is illustrated and described specific examples in accordance with the invention.